1. Technical Field
The present invention relates to an airbag device for a front passenger's seat, and particularly relates to an airbag device for a front passenger's seat that is equipped with a top mount-type airbag module.
2. Related Art
In an airbag device for a front passenger's seat recited in Japanese Patent No. 4,946,899, a top mount-type airbag module is disposed below an upper wall portion of an instrument panel. In this airbag module, the airbag is inflated with gas that is jetted out by an inflator, an airbag door provided in the upper wall portion of the instrument panel is opened by inflation pressure from the airbag, and the airbag is inflated upward through an aperture formed in the upper wall panel by the opening of the airbag door. The airbag that is inflated to the upper side of the instrument panel abuts against a windshield, inflates and expands toward the vehicle rearward side, and restrains a passenger while being supported by the windshield.
However, in a vehicle in which the roof is set lower or the like with a view to improving fuel economy or the like, the upper wall portion of the instrument panel is in some cases set to a lower position. In this kind of vehicle, the installation position of a top mount-type airbag module may be set to a low position that is further downward from the windshield. In this case, for the inflated and expanded airbag to abut against and be supported by the windshield, the volume of the airbag needs to be increased, and the expansion speed of the airbag may be slowed. Moreover, it is more difficult to make support of the airbag by the windshield stable, and the airbag may be more susceptible to being pushed in toward the vehicle forward side when restraining a passenger. Thus, there is scope for improvement in the matter of making passenger restraint performance by an airbag excellent.
In consideration of the circumstances described above, an object of the present invention is to provide an airbag device for a front passenger's seat that may make passenger restraint performance by the airbag excellent even when an installation position of a top mount-type airbag module is low.